Chock block unit



FIG. 1 is a front elevational view of a chock block unit showing my newdesign, it being understood that the broken lines are for illustrativepurposes only and form no part of the claimed design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a greatly enlarged left side elevational view thereof;

FIG. 4 is a greatly enlarged right side elevational view thereof;

FIG. 5 is an enlarged top plan view thereof; and,

FIG. 6 is an enlarged bottom plan view thereof.

The ornamental design for a chock block unit, as shown and described.